Abstract
•Initial growth of sonoluminescence (SL) and sonochemical (SC) activity is investigated.•SC active bubble population grows at a much faster rate than SL bubble population at 358kHz and 647kHz.•The growth rates of SL and SC active bubble populations are similar at 1062kHz.•The difference in the resonance size range of SL and SC active bubbles is responsible for this trend.•These results may be useful in controlling the growth of acoustic cavitation activity.
The initial growth of acoustic cavitation activity is important in some applications such as therapeutic and diagnostic medicine. The initial growth of cavitation activity has been investigated using sonoluminescence and sonochemical activity (sonochemiluminescence) at 358kHz, 647kHz and 1062kHz and at 5W, 15W and 30W applied power levels. The growth of sonochemically active bubble population is found to be much faster than that of sonoluminescence bubble population at 358kHz and 647kHz whereas almost similar growth rate is observed at 1062kHz for both bubble populations. This suggests that the cavitation bubble resonance size ranges of sonoluminescence and sonochemically active bubbles are different at 358kHz and 647kHz, whereas they have similar size range at 1062kHz. At 358kHz and 647kHz, relatively smaller bubbles become chemically active. Possible reasons for such observations have been discussed. The data presented and discussed in this study may be useful in controlling the growth of cavitation bubble population in addition to enhancing the knowledge base in cavitation science.